Alarm device.



'PATENTED JUNE 23, 1908. G. W. MAOKENZIE.

ALARM DEVICE.

APPLICATION FILED NOV. 30, 1907.

the gas-distributing pipe.

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GEORGE MACKENZIE, OF BEN AVON, PENNSYLVANIA, ASSIGNOR TO BUTLER MANUFAC- TURING COMPANY, OF BUTLER, PENNSYLVANIA.

ALARM DEVICE.

Specification of Letters Patent.

Patented June 23, 1908.

To all whom it may concern:

Be it known that I, GEORGE W. MACKEN- ZIE, a citizen of theUnited States, residing at Ben Avon, in the county of Allegheny and State of Pennsylvania, have invented certain new and useful Improvements in Alarm De vices, of which the following is a specification, reference being had therein to the accom anying drawing.

y invention refers to an improvement in alarm devices for the purpose of indicating either high or low pressure, or the absence of any pressure, in a gas main, by means of mechanism actuated directly by the pressure of the gas from the main or any distributing connection, and is constructed and adapted to operate in the manner hereinafter described.

Referring-to the drawings Figure 1 is a view in side elevation showing the apparatus in position for operation in connection with Fig. 2 is a longitudinal sectional view showing the device in normal position. Fig. 3 is a similar view showingkthe effect of the high gas pressure to make t e contact with the terminals establishing the alarm circuit. Fig. 4 is a similar view showing the eflect of low pressure or lack of any pressure to eflect the same result.

Figs. 5 and 6 are detail views showing amodi fied construction. employing a temporary lock for breakin the alarm circuit. Fig. 7 is a detail lan view of the slotted insulatin block on the end of the abutment stem.

The invention has in view to provide means whereby gas pressure, acting upon a movable dam or diaphragm, operates to establish, electrical communication with any same result when the diaphragm is abnor-,

suitable alarm, as a bell, when the dipflphragm is abnormally, extended, and to e ect the mally retracted.

The device consists generally of a casing com osed of two opposltely disposed inclosing s ells 2 and 3, referably circular and engaging between t eir flanges 4, a movable dam of an suitable type, which may convenientlye in .the form of a rubber diaphragm 5.

At its inner or pressure side the device is connected with the pi e system or main by a connection 6 attache to shell 2 whereby gas pressure is communicated to the interior and said ends.

bearing extension -7 between which and the diaphragm is interposed a' compression sprmg 8, preferably a coiled spring, surrounding stem 9. Said stem 9 is connected with the diaphragm at its center in any suitable manner as indicated at 10 and extends beyond the opposite side as indicated at 11 into the pipe 6, in which it has a sliding bearing, with free clearance for the gas. By this construction stems 9 and 11 support and centralize the mechanism and stem 9 is provided with means for making the electrical contact with the other elements.

12 is a rigid uide stem extending outwardly .beyond t e bearing 7, into which it Ina be secured as shown, upon which stem is s idingly mounted an insulating block 13 having frictional engagement with the stem, in whicliis mounted a contact member 14 adapted by its inner end to make electrical contact with the shell 3 or with its extension 7 when retracted as shown in Fig. 4. Stem 14 at its outer portion is bent downwardly as shown, extending through a slotted insulati'ng block 15 mounted on the other end of stem 9, and is provided at its terminal with the bindingpost 16 for attachment of one of the alarm circuits. I

Insulating block 15 is provided with a longitudinal slot 17 through which asses stem 14 and which slot is of sufficient ength to permit of considerable movement of the diaphragm 5 without making contact with the desired-limitations, defined by the ends of slot 17 or by the contacting devices set in Stem 9 extends by contact terminal 18 through. the end of block 15 and projects terminal 18 into contact with stem 14 when the diaphragm is unduly extended, as, shown in Fig. 3, and block 15 is preferably provided at its outer end with a temper screw 19 whereby inward range of movement of diaphragm .5 before stem 14 is also drawn in by contact of screw 19 to actuate the alarm may be adjusted. 20 is the alarm, as a bell, with which communicates the circuit wire 21, either directly as indicated in dotted lines in Fig. 1, but preferably through a supporting post 22 aving an insulated mountmg at 23- in the flanges 4 of shells 2 and 3, from any portion of which stem 22 as the outer end, and by a binding nut, connection ma be made to the bell 20 as clearly shown. uch connection, by reason of the'insulation, is entirely lndependent of the casing shells 2 and 3, and for I a the purpose of establishing the circuit in any and to the bell 20, as shown in Fig. 1.

The operation of the device as thus constructed 1s as follows: The desired normal pressure of gas being determined, block 13 carrying stem 14 is moved outwardly from contact as in Fig. 2, and so long'as the pres sure behind the diaphragm remains normal the device will remain inoperative. Should the ressure become excessive the diaphragm will e extended as in Fig. 3, making contact by terminal 18 with stem 14, whereu on current will be established therethroug to bell 20, battery 25 and either shell 2 or 3 tostem 9, resulting in ringing the alarm.

In case of a decrease-in pressure or the absence of any ressure whatever, spring 8 will retract diap ragm 5, whereupon stem 14 will be engaged by binding screw 19 or the outer end of slotted bar 15, throwing stem '14 and its supporting block 13 backwardly along guiding stem 12, making contact by the inner end of stem 14 with casing 7, thus establishing an alarm circuit through the casing 3, connection 2 1, battery 25, to hell 20 and its connection 21 to stem 14.

In Figs. 5 and 6 I have shown a modified construction for the purpose of holding stem 14 temporarily away from contact with bearing 7 of casing 3, after an alarm has been sounded upon a reduction of pressure so as to temporarily break the alarm circuit and stop the ringing of the bell, it being assumed that all gas connections have, 'upon notification by the alarm, been shut ofi. Such temporary locking device consists of an arm 26 pivo'tally mounted at 27 toinsulating block 13 and having a shouldered lip 28 at its inner end adapted to engage the u er edge of extension 7 or any other suita le element, to hold pin 14 away from contact. The same result may be secured upon the alarm being sounded due to excess pressure by merely moving insulating block 13 and stem 14 outwardly awa from contact withterminal 18, as indicate in dotted lines in Fig. 3, and with either construction it will be seen that the alarm having sounded, and the ordinary precautions having been taken againstaccident by shutting off the gas, the device may be set to arrest the soundlng of the alarm until normal conditions are again established. lln event of the ressure of the gas being reduced from the a normally high pressure, the stem 19 will merely travel'backwardly, due to the action of spring 8 and will push stem 14 inwardly to a position for operation for again sounding the alarm due to either cause, and in the event of abnormally low.

pressure and the reestablishment of normal pressure, causing the diaphragm and stem 9 to again travel outwardly, pivoted arm 26 will become detached and will fall wardly by gravity as shown in Fig. .6. With either construction the device will become automatically operative upon reestablishment of normal conditions of pressure.

The construction and operation of the device will be readily understood from the foregoing description. It provides a convenient and simple means for the object in view, it is capable of reliable operation under the various conditions'assumed, and in use has given highly satisfactory results.

It may be changed or varied in various features bythe skilled mechanic without 'de parture from the scope of the invention, and all'such changes are to be understood as being included within the scope of the following claims.

What I claim is:

1. An alarm device for fluid pressures confluid connection and a mova le dam having tacts, a relatively mova le contact element adapted to be engaged by either of said stem contacts, an alarm device, and an electrical connection from the movable contact element to the alarm, and from the alarm to the case, substantially as set forth.

2. An inclosing casin having a movable dam, a stem connecte with the movable dam provided with opposing contact terminals, 'a slidingly movable insulated contact arranged to engage the movable dam stem andcasing respectively, an alarm de contact, and a connection between the alarm source of energy, substantially as set forth.

3. An inclosing casing having a movable dam, a spring-controlled stem connected with the movable dam provided with opposing contact terminals, a slidingly movable insulated contact arranged to engage the contact terminals of the movable dam stem and casing res ectively, an alarm device, a connection t ereto from the insulated contact, and a connection between the alarm device and the shell with an intervening source of energy, substantially as set forth.

trical connection with an alarm device and having a supporting stem, and a relatively movable contact member slidin ly mounted by an insulatin block frictiona y engaging said stem and a so connected with the alarm device; of a movable fluid-actuated dam within the shell provided with a stem contacting with the shell and having a terminal adapted. to engage said contact member, substantially as set forth.

5. The combination with a shell in electrical connection with an alarm device and sisting of an inclosing case rovided with a device and the shell with an intervening downi a stem provided with s aced terminal convice, a connection thereto from the insulated vios 4. The cembination with a shell in eleca relatively movable insulating contact member 14 also connected with said alarm device, of a spring-retracted movable dam within the a shell provided with a stem in electrical connection with the shell and having a contact ing terminal 18 and a slotted insulating terminal extension embracing said contactmember 14, arranged to make electrical contact therewith in one direction of said terminal 18.and.toengage and shift it in the other direction and cause said contact member 14 to engage the shell, for the purpose described. I

6. The combination with ashell and an alarm device electrically connected therewith, of a supporting stem, a movable contact member .mounted by an insulating block on said stem, and a movable dam With- 1n the shell provided with a slidingstem in electrical connection with the shell, said stem having a slotted terminal adapted to electrically engage the movabl'e contact member on outward travel, and to draw it backwardly into contact with the shellon inward travel, substantially as set forth.

7. In a device of the class described, the combination with an inclosing shell having a fluid connection, a fluid-actuated movable dam within the shell having a movable contactin portion, and an insulating block slidably supported with relation to the shell and having a contact member arranged to co-act with said niovable contacting portion; of a locking arm pivoted to the insulating block adapted to hold it outwardly from the shell, and to fall by gravity when disengaged therefrom upon outward travel of the movable contacting portion of the movable dam, substantially as set forth.

In testimony whereof I afiix in presence of two witnesses.

Witnesses:

C. M. CLARKE, CHAs. S. LEPLEY.

my signature 

